OBJECTIVETo compare the clinical effect of different tapered gutta-percha root filling by warm vertical condensation with immediate postoperative radiographs and one year follow-up.

METHODS40 maxillary anterior teeth with single, straight canals were divided into two equal groups. The teeth were instrumented with Hero 642 rotary nickel-titanium files to a master file 0.06 taper No. 30. Group 1 was obturated with 0.02 tapered gutta-percha using System B for downpack and Obtura II for backfilling. Group 2 was the same but 0.06 tapered gutta-percha. Every tooth's X-ray radiographs of immediate postoperative and one year follow-up were taken. In order to compare the quality of root canal filling, the rate of filling material extrusion, and the rate of obturation of lateral canals in each group were evaluated by X-ray radiographs. The clinical effect of one year follow-up's radiographs of the two groups was compared too.

RESULTSThere was no significant difference in two groups on the quality of the root canal filling, obturation of lateral canals, and filling material extrusion. The success of the therapy was similar. But the 0.06 tapered gutta-percha group showed more quickly healing trend on apical periodontitis.

CONCLUSIONWhen single, straight root canals were obturated using warm vertical condensation, adaptively tapered gutta-percha showed better clinical effect.